Field of the Invention
The present invention relates generally to surgical navigation systems. More particularly, the present invention relates to a medical device for use in a surgical navigation system.
Related Art
Surgical navigation systems are employed in a variety of surgical applications, for example, in neurosurgery, oral, maxillofacial and facial surgery, ear nose and throat (ENT) surgery or also for limb implantation in orthopedic surgery. Based on three-dimensional patient image data, which are obtained by means of X-ray images, computer tomography (CT), magnetic resonance tomography (MRT) and/or positron emission tomography (PET), surgical navigation systems of this type enable the position of medical instruments to be visualized in real-time in the patient image data in order to thereby assist the surgeon during operable procedures.
To this end, it may be necessary to record and monitor the position and orientation of the patient or a specific body part on which a surgical procedure is to be carried out—also referred to as “tracking.” Conventional referencing devices, employed within such surgical navigation systems, for example, have been used usually comprising reference frames to which marking elements such as light-reflecting, spherical marker elements are attached. The light-reflecting spherical marker elements allow a stereo camera system of the navigation system to record the precise position and orientation of the referencing device.
Prior art reference frames are traditionally reusable units that may be subjected to a sterilization process after use. The marker elements of the reference frame may also be removed and replaced. As is often the case, for example, the reference frame contains mounting assembly structures to which the marker elements are mounted. However there are concerns in quality control processes to ensure total elimination of infectious diseases, such as mad cow disease, for example, during the aforementioned sterilization process of the reference frame and/or the marker elements. In addition, there exists a risk in breakage of the mounting assembly structures of the reference frame. Furthermore, such mounting assembly structures may become bent or skewed during removal or attachment of the marker elements. This introduces misalignment of the marker elements and, hence, possibly the reference frame itself for use in the surgical navigation system. Additionally, errors and inaccuracies in location, for example, are introduced giving rise to critical errors that may be introduced during a misaligned setup.
It is, therefore, an object of the present invention to overcome the deficiencies of the prior art to provide an improved reference frame capable of eliminating or greatly reducing errors/inaccuracies in misalignment during setup. It is a further goal of the present invention to provide a method and apparatus that achieves the elimination or reduction of the transfer of infectious diseases and other possible contaminants within the surgical navigation system. It is desirable to achieve a method and apparatus that maintains a dependable fixed position of marker elements mounted on the referencing frame during operational procedures that eliminates the need to recalibrate the system. Such reference frame should be easily and accurately reproducible.